This is A. Srinivasa Raghavan's English translation of Nadadur Ammal's Para Tattva Nirnaya. Nadadur Ammal, aka Vatsya Varadacharya, was a 12th century Sri Vaishnava Acharya. He was the grandson of Ramanujacharya’s nephew Nadadur Alwan, and he was one of the greatest experts on Ramanujacharya’s Sri Bhashya of all time. He had many famous disciples, including Kidambi Apullar, uncle and guru of Vedanta Desikan, and Vadakku Thiruveedhi Pillai, father and guru of Pillai Lokacharya. It is due to philosophical differences between Vedanta Desikan and Pillai Lokacharya that the Sri Vaishnava sect split up into Thenkalais and Vadakalais centuries later.
In any case, the Para Tattva Nirnaya is a work by Nadadur Ammal devoted to establishing Vishnu as the Para Tattva or supreme reality, which is an important tenet of Sri Vaishnavism. He analyzes a variety of scriptural verses to demonstrate this conclusion.
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